4.4 Kinetic Energy

4.4 Kinetic Energy


- Energy of moving object


- Factors that affect kinetic energy are mass and speed



So, the equation used to find kinetic energy calculates work done to give an object a known velocity from rest.


So, the equation is :


W=Fnet Δd ..... Since Fnet = m•a,


W = m•a Δd ..... Since a = (v2 – v1) / Δt,


..........................Since v1 = 0, then a = v2 / Δt


..........................Remember that, Δd = [ (v1+v2) Δt ] / 2


.................................Which becomes, Δd = v2• Δt / 2


W= m(v2 / Δt)( v2• Δt / 2)


W= ½ m(v^2)


Ek=½ m(v^2) ……Kinetic Energy = ½ • mass • velocity squared

So, m = mass of object (kg)
v = velocity of the object (m/s)
Ek = kinetic energy of the object (Joules)

Link: An old school video about kinetic energy , enjoy!
http://www.youtube.com/watch?v=zhX01toLjZs


By: Akshay Nair